Antenna apparatus

Abstract

There is disclosed an antenna apparatus used for satellite communication or the like and including an antenna rotating in an azimuth angle direction and an elevation angle direction, which can be miniaturized without using a slip ring for ensuring electrical connection between a stationary portion and a movable portion. A rotary member 3 is rotated by rotation of a motor 5 to rotate an antenna 11 about an azimuth axis. On the other hand, a motor 9 is rotated to rotate a rotary member 7, and a relative rotary shaft 14 is rotated by relative rotation between the rotary member 3 and the rotary member 7. The rotation of the relative rotary shaft 14 rotates the antenna 11 about an elevation angle axis by rotation transmission through a bevel gear 18 and a bevel gear 19.

What is claimed is:  
     
       1. An antenna apparatus, comprising: 
       a base portion;  
       a disk-shaped first rotary member supported on the base portion and provided rotatably about an azimuth axis;  
       a first motor provided on the base portion and for rotating the first rotary member;  
       a disk-shaped second rotary member supported on the base portion and provided rotatably about a same axis as the first rotary member;  
       a second motor provided on the base portion and for rotating the second rotary member;  
       a relative rotary shaft provided on the first rotary member and rotating by relative rotation between the first rotary member and the second rotary member; and  
       a rotation transmission portion for rotating an antenna provided on the first rotary member about an elevation angle axis by the rotation of the relative rotary shaft.  
     
     
       2. An antenna apparatus according to  claim 1 , wherein the second rotary member includes gear teeth formed on a circumference around its rotary axis, and the relative rotary shaft includes a gear provided at one end of the shaft and engaging with the gear teeth. 
     
     
       3. An antenna apparatus according to  claim 1 , wherein the relative rotary shaft includes a shaft member substantially parallel to the azimuth axis, and the rotation transmission portion includes a bevel gear provided at one end of the shaft member, and a bevel gear provided on an elevation angle rotary shaft of the antenna provided on the first rotary member. 
     
     
       4. An antenna apparatus according to  claim 1  wherein the second motor carries out drive control on the basis of an elevation angle setting table describing the relative rotation between the first rotary member and the second rotary member corresponding to an elevation angle of the antenna. 
     
     
       5. An antenna apparatus, comprising: 
       a base portion;  
       a first rotary member supported on the base portion and provided rotatably about an azimuth axis;  
       a first motor provided on the base portion and for rotating the first rotary member;  
       a second rotary member supported on the base portion and provided rotatably about a same axis as the first rotary member;  
       a second motor provided on the base portion and for rotating the second rotary member;  
       an antenna provided on the first rotary member and rotatably supported about an elevation angle axis; and  
       a link member for connecting a support point provided at a position of the antenna offset from the elevation angle axis and a support point provided on the second rotary member and for rotating the antenna about the elevation angle axis by relative rotation between the first rotary member and the second rotary member.  
     
     
       6. An antenna apparatus according to  claim 5 , wherein the link member includes spherical bearings at both its ends. 
     
     
       7. An antenna apparatus according to  claim 5 , wherein the second motor carries out drive control on the basis of an elevation angle setting table describing the relative rotation between the first rotary member and the second rotary member corresponding to an elevation angle of the antenna.